201220862 F3iyyuuD7TW 35485twf.doc/n 六、發明說明： 【發明所屬之技術領域】 本發明是關於一種平面揚聲器的驅動介面裝置。 【先前技術】 視覺與聽覺是人類最直接的兩種感官反應，因此長 久以來，科學家們極力的發展各種可再生視覺與聽覺的相 關系統。在目前’主要仍是由動圈式揚聲器來主宰整個市 場。但是隨著近幾年來人們對於感官品質的要求日益提 升，以及 3C 產品（Computer、communication、consumer electronics )在追求短小、輕薄的前提下，一種省電、輕薄、 可依人體工學需求設計的揚聲器，不管是搭配大尺寸的平 面揚聲器，還是小到隨身聽的耳機，立體聲的手機，在可 以預見的明天，此方面的技術將有大量的需要與應用的發 展。 目前電聲揚聲器分類主要分為直接、間接輕射型， • 而驅動方式大概分為動圈式、壓電式及靜電式揚聲器。動 圈式揚聲器目前使用最廣且技術成熟的類型，不過由於其 先天架構的缺點，並無法將體積扁平化，使得面對3C產 品越來越小及家庭劇院扁平化的趨勢，將不符需求。 壓電式揚聲器利用電壓材料的壓電效應，當附加一 電，於壓電材料所造成材料變形的特性，用來推動震動膜 發聲，此揚聲器雖然結構扁平微小化，但於聲音品 所限制。 201220862 r3iyyWD7TW 35485tWf.doc/n 機二=:= 二=): ^ , ^ ^ 只〜乂机要7整’利用正負雷煬 斤發生的靜電力，帶動振膜振動並將聲音輕射出去。、 統靜電式揚聲器的偏壓需達數百至上千 兩一， 單價及龐大體積的擴大機，並且在轉換的過^ 到將近四百伏特以上的電源，這種動的^ ^連接 產生相當高的功率消耗，因此無法普=的駆動電路將會 傳統的技術於量產上需以逐一完成個別單體，且 聲器基本都有-m定大小或外型的_ 量製造與降低成本，並且在外觀上無法達到軟^有^ 動電壓、以及可撓曲等特性。 【發明内容】 本毛明k供一種具有驅動介面裝置之平面揚聲芎， 其中驅動介面裝置用以接收—音訊訊號，並據以轉換後驅 動-平面揚聲器。此驅動介面裝置至少包含—阻抗元件與 :變壓器。此阻抗元件耦接到音訊訊號’並轉為一第一電 壓訊號。而變壓n雛到阻抗元件，並據以接㈣一電壓 汛號。此變壓器用以將第一電壓訊號轉為第二電壓訊號， 其中第二電壓訊號的位準高於第一電壓訊號，而第二電壓 訊號用以驅動平面揚聲器據以發出聲音。 該阻抗元件可為-電容、電阻、電感或其它等效元 201220862 rD lyyuvDlTW 35485twf.doc/n 件0 【實施方式】 在實施範例其中之一，揭示一種平面揚聲器的驅動介 面裝置。其中該平面揚聲器可為薄型平面揚聲器。該驅動 介面裝置可為被動式驅動介面褒置（Passive Driving Interface)。此驅動界面裝置適用於直接耦合到外部音源訊 號，並根據此音源訊號直接升壓後驅動平面揚聲器，而可 以不需外部的電源。 在實施範例其中之一所揭示的驅動介面裝置，可以採 用一阻抗元件耦合到外部音源訊號的方式。因為考慮平面 揚聲器的中高頻效應表現效果，因此，可經由電容耦合， 過濾低頻的訊號。在另一實施例中，若不考慮音源訊號的 頻率響應，則可直接以一電阻元件耦合到外部音源訊號。 在實施範例其中之一所揭示的驅動介面裝置，可採用 具升壓效果的變壓器，以便將耦接的外部音源訊號，升壓 到可驅動平面揚聲器的電壓範圍。而在一實施例中，可利 用調整變壓器的繞線比，而達到預定的變壓值。 為避免因連接到不同音源而因過大功率或是電壓導致 對平面杨聲器的損害，在一實施例中，可加入一限壓電路， 配置於一次側(低壓）的原始電壓輸入端，或是配置在二次 側（高壓）的高壓輸出端，以控制所需要的穩定電壓值。而 為避免訊號的突波等雜訊，造成整個裝置的損害，在實施 範例其中之一所揭示的驅動介面裝置，可加入過壓保護電 201220862 r^iyyuui7TW 35485twf.doc/n 路。 上述實施範例其中之一所揭示的驅動介面裝置，可將 具過濾低頻訊號的電容、限壓電路、與過壓保護電路整合 在一起，而達到實現升壓、分音(濾頻)及保護等三合一: 平面揚聲器之驅動介面裝置功能。 。在本發明所提出實施範例其中之一所揭示的平面揚聲 器f驅動介面裝置，接下來，就外部音源訊號是來自於例 如疋動圈式擴大機的輸出，而驅動的對象為具有駐極體震 動膜的平面揚聲器進行說明，但並非以此為限制。 外。卩音源訊號來自動圈式擴大機的輸出，不僅可以減 少驅動模組硬體空間及成本，更有利於消費者直接將平面 器整合至現有之動圈式音響系統，強化原有系統中高 音音響效果，實現一高品質之音響系統。透過這樣的設計， 可以讓平面揚聲器在音響系統設計能普遍受到歡迎與使 用。 ^參照圖1，其為依照本實施例所提出的平面揚聲器之 ，動”，褒置之架構示意圖。以下每—實施例之平面揚聲 器可為薄型平面揚聲器或其它等效平面揚聲器。驅動介面 裳^了為被動式驅動介面裝置或其它等效驅動介面裝置。 此驅動Μ面裴置120是介於音響驅動裝置100與平面揚聲 器130之間。驅動介面裝置12〇是採用被動式驅動介面裝 置。此驅動介面裝置適用於直接耦合到音響驅動裝置100 =斤^出的g源訊號，並將音源訊號升壓後用以驅動平面揚 聲态130。而此驅動介面裝置12〇與傳統靜電式揚聲器的 201220862 rDiyyWD7TW 35485twf.doc/n 驅動裝置抑。傳統靜電式揚聲㈣軸裝置 m運將近_伏特的輸人，這也是靜電^ 八不日及的原因之-。但本實施例所提出的驅動 ^裝置120，不需要外加電源，因此可適用於既有 源輸出，例如動圈式音響系統的放Α||輸出、車立二 =輸出、或是甚至-般的聰播放器的輸出都適用^ 朱構。201220862 F3iyyuuD7TW 35485twf.doc/n VI. Description of the Invention: [Technical Field] The present invention relates to a driving interface device for a planar speaker. [Prior Art] Vision and hearing are the two most direct sensory responses of human beings. Therefore, scientists have been developing various related systems of reproducible vision and hearing for a long time. At present, it is still mainly dominated by moving coil speakers to dominate the market. However, with the increasing demand for sensory quality in recent years, and 3C products (Computer, communication, consumer electronics) in the pursuit of short, light and thin, a power-saving, lightweight, ergonomically designed speakers Whether it is with large-size flat speakers, small headphones, stereo phones, and foreseeable tomorrow, this technology will have a lot of needs and applications. At present, the classification of electroacoustic speakers is mainly divided into direct and indirect light-emitting types. • The driving methods are roughly classified into moving coil type, piezoelectric type and electrostatic type speakers. Dynamic coil loudspeakers are currently the most widely used and mature type of technology, but due to the shortcomings of their innate architecture, they are not able to flatten the volume, making the trend towards 3C products becoming smaller and flattering in home theaters. Piezoelectric speakers use the piezoelectric effect of the voltage material. When a new electric is applied, the deformation of the material caused by the piezoelectric material is used to promote the sound of the vibrating film. Although the speaker is flat and miniaturized, it is limited by the sound product. 201220862 r3iyyWD7TW 35485tWf.doc/n Machine 2 =:= 2 =): ^ , ^ ^ Only ~ 乂 machine to 7 whole 'Using the electrostatic force generated by positive and negative Thunder jin, drive the diaphragm vibration and light out. The electrostatic actuators have a bias voltage of hundreds to thousands, a unit price and a large volume expansion machine, and the conversion of the power supply to nearly 400 volts or more, the dynamic ^ ^ connection is quite high The power consumption, so it is impossible to use the conventional technology to mass-produce individual monomers one by one, and the sounder basically has -m size or shape _ quantity manufacturing and cost reduction, and In appearance, it is impossible to achieve the characteristics of soft voltage, flexible voltage, and flexibility. SUMMARY OF THE INVENTION The present invention provides a planar speakerphone having a drive interface device for receiving an audio signal and converting the rear drive-plane speaker accordingly. The drive interface device includes at least an impedance component and a transformer. The impedance element is coupled to the audio signal ' and converted to a first voltage signal. And the transformer n is cut into the impedance component, and according to the (four) one voltage nickname. The transformer is configured to convert the first voltage signal into a second voltage signal, wherein the second voltage signal is higher in level than the first voltage signal, and the second voltage signal is used to drive the flat speaker to emit sound. The impedance element can be a capacitor, a resistor, an inductor or the like. 201220862 rD lyyuvDlTW 35485twf.doc/n 0 [Embodiment] In one of the embodiments, a driving device for a planar speaker is disclosed. The flat speaker can be a thin flat speaker. The drive interface device can be a passive drive interface. The drive interface device is suitable for directly coupling to an external sound source signal, and directly boosts the flat speaker according to the sound source signal, and does not require an external power source. In the driving interface device disclosed in one of the embodiments, a manner in which an impedance element is coupled to an external sound source signal can be employed. Because of the mid-high frequency effect of the planar speaker, the low frequency signal can be filtered via capacitive coupling. In another embodiment, if the frequency response of the sound source signal is not considered, the external sound source signal can be directly coupled by a resistive element. In the driving interface device disclosed in one of the embodiments, a boosting transformer can be used to boost the coupled external sound source signal to a voltage range that can drive the planar speaker. In one embodiment, the winding ratio of the transformer can be adjusted to achieve a predetermined voltage transformation value. In order to avoid damage to the planar speaker due to excessive power or voltage due to connection to different sound sources, in one embodiment, a voltage limiting circuit may be added to the primary voltage input of the primary side (low voltage). Or it is configured on the secondary side (high voltage) high voltage output to control the required stable voltage value. In order to avoid the noise such as the signal surge, the damage of the whole device is caused. In the driving interface device disclosed in one of the implementation examples, the overvoltage protection circuit 201220862 r^iyyuui7TW 35485twf.doc/n can be added. The driving interface device disclosed in one of the above embodiments can integrate a capacitor with a low-frequency filtering signal, a voltage limiting circuit, and an overvoltage protection circuit to achieve boosting, splitting (filtering) and protection. Three-in-one: The function of the drive interface device of the flat speaker. . In the planar speaker f driving interface device disclosed in one of the embodiments of the present invention, the external sound source signal is from an output of, for example, a slewing ring expander, and the object to be driven is electret vibration. The flat speaker of the film is described, but not limited thereto. outer. The sound source signal to automatically output the output of the coil amplifier not only reduces the hardware space and cost of the drive module, but also facilitates the consumer to directly integrate the plane to the existing dynamic sound system, and strengthens the high-pitched sound in the original system. The effect is to achieve a high quality sound system. Through this design, flat speakers can be generally welcomed and used in sound system design. Referring to FIG. 1 , which is a schematic diagram of the structure of a planar speaker according to the present embodiment, the planar speaker of each of the following embodiments may be a thin planar speaker or other equivalent planar speaker. The passive driving interface device or other equivalent driving interface device is disposed between the audio driving device 100 and the planar speaker 130. The driving interface device 12 is a passive driving interface device. The interface device is adapted to directly couple to the g source signal of the audio driving device 100, and boost the audio signal to drive the planar speaker state 130. The driving interface device 12〇 and the conventional electrostatic speaker 201220862 rDiyyWD7TW 35485twf.doc/n drive device. The traditional electrostatic speaker (four) axis device m transports nearly _ volts of input, which is also the reason for the static electricity. But the drive device proposed in this embodiment 120, no need for external power supply, so it can be applied to both active output, such as the dynamic output of the moving coil sound system | | output, car two = output, or even - like output Cong player are applicable ^ Zhu configuration.
本發明阻抗元件可為電容、電阻或其等效之元件，各 =例以電容為說明，但不為電容觸限。其中該阻抗元 為-電容器’用崎該音觀舰械波纽後轉為該 電壓訊號。而如該阻抗元件為-電阻it件，用以對該 曰訊訊唬分壓處理後轉為該第一電壓訊號。 在此實施例的.驅動介面裝置中，可加入包括可過濟低 ，訊號的電容、限壓電路、或過壓保護電路其巾之一厂或 ^二者整合在—起，耐到實現升壓、分音(義)及保 瘦專功能的平面揚聲ϋ之驅動介面裝置。鮮來之各實施 例’將以不同實施例的運用架構示意圖加以說明 ，但並非 以此為限制。 请參照圖2Α與2Β，是說明在一實施例中所提出的平 面揚聲器之驅動介面裝置之架構示意圖。冑2Α是說明本 實靶例的驅動介面裝置12〇Α是配置於音響驅動裝置1〇〇 與平面揚聲器130之間的連接示意圖。根據音響驅動裝置 joo的正負端所輸出的音源訊號112與114(如圖所式的 ιη+’與“ln·”），經過驅動介面裝置ι2〇α的升壓與分音操作 201220862 35485twf.d〇c/n 後’輸出極性互異的驅動訊號122與124到平面揚聲器 130，以便據以驅動而發出聲音。 圖2B是說明本實施例的驅動介面裝置120A的電路結 構示意圖及平面揚聲器130的等效結構示意圖。此驅動介 面裝置120A至少包含一電容器121及一變壓器123。在此 變壓器123中，一次側(低壓)與二次侧（高壓)的繞線圈數比 為1:N，可將一次側動圈式揚聲器的低電壓升到n倍的高 電壓。 此外’電容器121直接與變壓器123本身的寄生電感結 合成高音濾波器，進而實現高音升壓轉換器之功能。而傳 統靜電式揚聲器的驅動裝置，需要相當複雜的電路設計， 至少包括多個複雜之電晶體、運算放大器、二極體、電阻、 電容、電感組成之升壓電路及濾波電路等電子元件。相較 於在本實施例所提出的驅動介面裝置120A，利用二個元件 (電容、變壓器）即可實現相同功能與效果，初步估算約可 省下80%左右的零件成本(Bin 0f Materials，BOM)，對於平 面揚聲器之產品價格競爭力提升將有大幅幫助。 、 而對於本實施例中的平面揚聲器13〇,可等效為串聯的 一匹配電阻132與一等效負載電容134。此平面揚聲器13〇 具有單一或多個平面揚聲器單體。以平面揚聲器13〇且 個平面揚聲H單體為例，基本的操作原理是利4倫定 律’通常是以兩個電極膜片面對面擺放，在兩片膜片二中 間加上-片透過駐電製程將電荷儲存於駐極體層之帶電振 膜，。當對上下兩片電極膜片施加一交流電壓時，令 會被其上下電場牽引而產生位移，藉由彼此互相的吸引排 201220862 r J j7TW 35485twf.doc/n 斥作用推動空氣’進而發出聲音。由於單體質量輕，且振 動分散小，所以在中高音方面效果不錯’可輕易獲得清澈 透明的中高音。 平面揚聲器130要發出好的聲音，除了需要好的揚聲 器單體外’驅動介面裝置120A亦是另一個考慮的因素。 由於軟性揚聲器須要高電壓低電流之功率驅動的方式來達 到較大的音量及較佳的頻率響應曲線，相對於傳統低電壓 馨 高電流之動圈式揚聲器擴大器而言，並不能直接以高電壓 低電流方式驅動’因此需藉驅動介面裝置120A之設計， 透過升壓電路將擴大器之低壓訊號轉換為高壓訊號，方能 驅動平面揚聲器發出聲響。除此之外，由於平面揚聲器13〇 的單體適合發出中高音域音頻訊號，因此透過驅動介面裝 置120A升壓同時’亦須將低頻音訊訊號濾除，再將高壓 之中高音頻訊號送到平面揚聲器130驅動發聲。而上述驅 動介面裝置120A的電容器121與變壓器123本身的寄生 電感可結合成高音慮波器，進而實現高音升壓轉換器之功 • 能。 請參照圖3A與3B，是說明另一實施例中所提出的平 面揚聲器之驅動介面装置之架構示意圖。本實施例架構上 與圖2A與2B類似，相同元件以相同符號表示，在此不再 冗述。圖3A說明本實施例的驅動介面裝置12〇b是配置於 音響驅動裝置100與平面揚聲器13〇之間。而圖3B是說 明本實施例的驅動介面裝置120B的電路結構示意圖。此 驅動介面装置120B包含電容器HI、變壓器123以及限壓 201220862 r〕iyyW37TW 35485twf.doc/n 器125。此驅動介面裝置12〇B除了具備圖2B所具有之電 容器121及變壓器123外’更整合限壓器125在變壓器123 的一次側(低壓)端，以作為平面揚聲器13〇限壓保謾的元 件。此限壓器125在一實施例中，可採用極性相反對接的 兩個一極體或是齊納二極體(zenor diode)所組成，以便限制 兩j的電壓值，但亦可由多個二極體或是其他的組合，只 要能達到限制雙端電壓差值都屬本實施例之範疇。 了參照圖4A與4B，是說明再一實施例中所提出的平 面揚聲器之驅動介面裝置之架構示意圖，本實施例架構上 與圖3八與3B類似，相同元件以相同符號表示，在此不再 冗述。圖4八說明本實施例的驅動介面裝置120C是配置於 音響驅動裝置1〇〇與平面揚聲器13〇之間。而與圖3A與 3B的差異在於限壓器125配置在變壓器ι23的二次側（高 壓)端’所以限壓器125採用的限壓元件必須選擇高於圖 3B所不的限壓器125元件，以符合輸出到平面揚聲器13〇 的驅動訊號122與124電壓值。 請參照圖5A與5B，是說明另一實施例中所提出的平 面揚聲器之驅動介面裝置之架構示意圖。本實施例架構上 與圖2A與2B類似，相同元件以相同符號表示，在此不再 冗述。圖5A說明本實施例的驅動介面裝置120D是配置於 音響驅動裝置1〇〇與平面揚聲器13〇之間。而圖5B是說 明本實施例的驅動介面裝置120D的電路結構示意圖。此 驅動介面裝置120D包含電容器121、變壓器123以及保護 電路127。此驅動介面裝置120D除了具備圖2B所具有之 201220862 rD iyyuu^7TW 35485twf.doc/n 電容器121及變壓器123外，更整合保護電路127在變壓 器123的一次側(低壓)端，以作為平面揚聲器13〇防止突 波破壞的保謾電路元件。 請參照圖6A與6B，是說明再一實施例中所提出的平 面揚聲器之驅動介面裝置之架構示意圖。本實施例架構上 與圖5A與5B類似，相同元件以相同符號表示，在此不再 冗述。圖6A說明本實施例的驅動介面裝置12〇e是配置於 音響驅動裝置100與平面揚聲器130之間。而與圖6A與 6B的差異在於保護電路127配置在變壓器123的二次侧 (高壓)端，所以保護電路127採用的突波保護電路元件必 須考慮到容忍比較高的操作電壓值。 請參照圖7A與7B ’是說明另一實施例中所提出的平 面揚聲之驅動介面裝置之架構不意圖。本實施例架構上 與前述實施例類似，相同元件以相同符號表示，在此不再 冗述。圖7A說明本實施例的驅動介面裝置12〇1?是配置於 音響驅動裝置100與薄型平面揚聲器130之間。而圖7B 是說明本實施例的驅動介面裝置12〇F的電路結構示意 圖。此驅動介面裝置120F包含電容器121、變壓器123、 限壓器125以及保護電路127。此驅動介面裝置120F除了 具備圖2B所具有之電容器丨21及變壓器123外，更整合 限壓器125以及保護電路127分別位於變壓器123的一次 側(低壓)端與二次側（高壓)端，以作為平面揚聲器13〇防止 突波破壞的保護電路元件。當然，如前些實施例所述，只 要選擇適當的元件組成，限壓器125以及保護電路127可 11 201220862 r j i^^wj7TW 35485twf.doc/n 配置在變壓器123的二次側(低壓)端或是一次側（高壓)端 任意的組合配置，並不受限制。 保護電路12 7可以是一種突波保護器（s ur g e protectionThe impedance element of the present invention can be a capacitor, a resistor or an equivalent component thereof, each of which is described by a capacitor, but is not capacitively limited. Wherein the impedance element is -the capacitor' is converted to the voltage signal by the sound of the ship. For example, the impedance component is a resistor component for converting the signal to the first voltage signal after the voltage is divided. In the driving interface device of this embodiment, a capacitor, a voltage limiting circuit, or an overvoltage protection circuit including a low-voltage, signal-proof circuit can be added, and the factory can be integrated into the device. Boost, split (sense) and thin-skinned drive interface device. The various embodiments will be described with reference to the operational architecture of the different embodiments, but are not intended to be limiting. Referring to Figures 2A and 2B, there is shown a schematic structural view of a driving interface device for a planar speaker proposed in an embodiment. The driving interface device 12A of the actual target example is a connection diagram disposed between the acoustic driving device 1A and the planar speaker 130. According to the sound source signals 112 and 114 outputted by the positive and negative ends of the audio driving device joo (as shown in the figure, ηη+' and "ln·"), the boosting and sounding operation of the driving interface device ι2〇α is 201220862 35485twf.d After 〇c/n, the drive signals 122 and 124 having mutually different polarities are output to the planar speaker 130 so as to be driven to emit sound. Fig. 2B is a schematic view showing the circuit configuration of the driving interface device 120A of the present embodiment and an equivalent structure of the planar speaker 130. The driving interface device 120A includes at least a capacitor 121 and a transformer 123. In this transformer 123, the ratio of the number of windings of the primary side (low voltage) to the secondary side (high voltage) is 1:N, and the low voltage of the primary side moving coil speaker can be raised to a high voltage of n times. In addition, the capacitor 121 directly combines with the parasitic inductance of the transformer 123 itself to form a treble filter, thereby realizing the function of the treble boost converter. The driving device of the conventional electrostatic speaker requires a relatively complicated circuit design, and at least includes a plurality of complicated electronic components such as a transistor, an operational amplifier, a diode, a resistor, a capacitor, an inductor, and a filter circuit. Compared with the driving interface device 120A proposed in the embodiment, the same function and effect can be realized by using two components (capacitance, transformer), and the initial estimation can save about 80% of the component cost (Bin 0f Materials, BOM). ), the price competitiveness of flat-panel speakers will be greatly improved. For the planar speaker 13A in this embodiment, it can be equivalent to a matching resistor 132 and an equivalent load capacitor 134 connected in series. This flat speaker 13 has a single or multiple flat speaker unit. Taking a flat speaker 13 〇 and a flat speaker H monomer as an example, the basic operating principle is that the four-pole law is usually placed face-to-face with two electrode diaphragms, and the film is inserted in the middle of the two diaphragms. The electrification process stores the charge in the charged diaphragm of the electret layer. When an alternating voltage is applied to the upper and lower electrode diaphragms, the upper and lower electric fields are pulled to generate displacement, and the mutual attraction is caused by the mutual attraction of the air. Due to the light weight of the monomer and the small dispersion of vibration, it works well in the middle and high sounds. It is easy to obtain a clear and transparent mid-high pitch. The flat speaker 130 is to emit a good sound, and the drive interface device 120A is another factor to be considered in addition to the need for a good speaker unit. Because soft speakers require high voltage and low current power driving to achieve a large volume and a better frequency response curve, compared to the traditional low voltage Xin high current moving coil speaker amplifier, it can not be directly high The voltage low current mode is driven. Therefore, the design of the driving interface device 120A is required to convert the low voltage signal of the amplifier into a high voltage signal through the boosting circuit to drive the sound of the planar speaker. In addition, since the single speaker of the flat speaker 13 is suitable for emitting the mid-high-range audio signal, the boosting of the low-frequency audio signal is also required to be filtered by the driving interface device 120A, and then the high-definition high-audio signal is sent to the plane. The speaker 130 drives the sound. The parasitic inductance of the capacitor 121 of the driving interface device 120A and the transformer 123 itself can be combined into a high-frequency filter, thereby realizing the function of the treble boost converter. 3A and 3B are schematic diagrams showing the structure of a driving interface device for a planar speaker proposed in another embodiment. The present embodiment is similar to that of Figs. 2A and 2B, and the same elements are denoted by the same reference numerals and will not be redundantly described herein. Fig. 3A illustrates that the driving interface device 12A of the present embodiment is disposed between the acoustic driving device 100 and the planar speaker 13A. 3B is a schematic diagram showing the circuit structure of the driving interface device 120B of the present embodiment. The driving interface device 120B includes a capacitor HI, a transformer 123, and a voltage limiting 201220862 r]iyyW37TW 35485twf.doc/n device 125. In addition to the capacitor 121 and the transformer 123 of FIG. 2B, the driving interface device 12B is further integrated with the voltage limiter 125 at the primary side (low voltage) end of the transformer 123 to serve as a planar speaker 13 . In one embodiment, the voltage limiter 125 may be formed by two poles or zenor diodes of opposite polarity to limit the voltage values of the two j, but may also be multiple Polar bodies or other combinations are within the scope of this embodiment as long as the limit of the double-ended voltage difference can be achieved. Referring to FIG. 4A and FIG. 4B, FIG. 4A and FIG. 4B are schematic diagrams showing the structure of a driving interface device for a planar speaker according to another embodiment. The present embodiment is similar in structure to FIG. 3 and FIG. 3B, and the same components are denoted by the same symbols. More details. Fig. 4 is a view showing that the driving interface device 120C of the present embodiment is disposed between the acoustic driving device 1A and the planar speaker 13A. The difference from FIG. 3A and FIG. 3B is that the voltage limiter 125 is disposed at the secondary (high voltage) end of the transformer ι23. Therefore, the voltage limiting component used by the voltage limiter 125 must select a voltage limiting device 125 higher than that of FIG. 3B. To match the voltage values of the drive signals 122 and 124 output to the flat speaker 13〇. 5A and 5B are schematic diagrams showing the structure of a driving interface device for a planar speaker proposed in another embodiment. The present embodiment is similar to that of Figs. 2A and 2B, and the same elements are denoted by the same reference numerals and will not be redundantly described herein. Fig. 5A illustrates that the driving interface device 120D of the present embodiment is disposed between the acoustic driving device 1A and the planar speaker 13A. 5B is a schematic diagram showing the circuit structure of the driving interface device 120D of the present embodiment. The drive interface device 120D includes a capacitor 121, a transformer 123, and a protection circuit 127. The driving interface device 120D has a 201220862 rD iyyuu^7TW 35485twf.doc/n capacitor 121 and a transformer 123 as shown in FIG. 2B, and a more integrated protection circuit 127 at the primary side (low voltage) end of the transformer 123 as a planar speaker 13谩Protection circuit components that prevent surge damage. 6A and 6B are schematic diagrams showing the structure of a driving interface device for a planar speaker proposed in still another embodiment. The present embodiment is similar to that of Figs. 5A and 5B, and the same elements are denoted by the same reference numerals and will not be redundantly described herein. Fig. 6A illustrates that the driving interface device 12A of the present embodiment is disposed between the acoustic driving device 100 and the planar speaker 130. The difference from Figs. 6A and 6B is that the protection circuit 127 is disposed at the secondary side (high voltage) terminal of the transformer 123, so that the surge protection circuit element employed by the protection circuit 127 must take into account a relatively high operating voltage value. 7A and 7B' are schematic views for explaining the structure of the driving device of the planar speaker proposed in another embodiment. The present embodiment is similar in structure to the foregoing embodiment, and the same elements are denoted by the same reference numerals and will not be redundantly described herein. Fig. 7A illustrates that the driving interface device 12〇1 of the present embodiment is disposed between the acoustic driving device 100 and the thin planar speaker 130. Fig. 7B is a schematic view showing the circuit configuration of the driving interface device 12A of the present embodiment. The drive interface device 120F includes a capacitor 121, a transformer 123, a voltage limiter 125, and a protection circuit 127. The driving interface device 120F has a capacitor 丨21 and a transformer 123 as shown in FIG. 2B, and the integrated voltage limiting device 125 and the protection circuit 127 are respectively located at the primary side (low voltage) end and the secondary side (high voltage) end of the transformer 123. A protective circuit element that acts as a planar speaker 13 to prevent glitch damage. Of course, as described in the foregoing embodiments, the voltage limiter 125 and the protection circuit 127 can be disposed on the secondary side (low voltage) side of the transformer 123 or as long as the appropriate component composition is selected, or 201220862 rji^^wj7TW 35485twf.doc/n. It is an arbitrary combination configuration of the primary side (high voltage) side and is not limited. The protection circuit 12 7 can be a surge protector (s ur g e protection
Device)，為電子設備突波防護中不可缺少的一種裝置，常 稱為“過電壓保護器”。突波保護器的作用是把竄入信號傳 輸線的瞬時過電壓限制在設備或系統所能承受的電壓範圍 内，保護被保護的設備或系統不受衝擊而損壞。突波保護 器的類型和結構按不同的用途有所不同，但至少應包含一 個非線性電壓限制元件。用於突波保護器的基本元件有例 如放電間隙、充氣放電管、壓敏電阻、抑制二極體和扼流 線圈等。突波保護器可以是例如限壓型保護器，其工作原 理是當沒有瞬時過電壓時為高阻擾，但隨突波電流和電壓 的增加其阻抗會不斷減小，其電流電壓特性為強烈非線 性。用作此類裝置的元件有氧化鋅、壓敏電阻、抑制二極 體、齊納二極體等。 上述的多個實施例中，所揭露具有限壓保謾功能之平 面揚聲器之驅動介面裝置，除了可具備電容器及變壓器元 件外，亦可整合限壓器與突波保護器作為平面揚聲器限壓 保謾之元件，因此，即使經過變壓器將訊號放大，可進一 步提供不會超過平面揚聲器的最高額定電壓，而對裝置造 成永久性損害。 12 201220862 r j iy^uuj7TW 35485twf.doc/n 上述的多個實施例中，所驅動的平面揚聲器，請參照 圖8所示的結構’為說明一實施例中的平面揚聲器之示意 圖。 對於位在任兩層相鄰的支撐體之間的振膜81()，平面 揚聲器802可具有幾個工作區。振膜810的兩邊能以相同 方式定義或以不同方式定義其工作區。所繪示之音室結構 可具有兩個腔室空間’以便產生揚聲器的共鳴音場或效 應，其中一個位於振膜810的上方且一個位於其下方。揚 鲁 聲器802可具有多個支撐體840、870，這些支標體840 : 870可設計成具有特定的形狀且放置在上下兩腔室空間之 内，以便分別支撐開孔電極820與振膜810，及支撐基底 860與振膜810。在一實施例中，圖8之上腔室空間可以是 傳聲孔區域842，並且在傳聲孔區域842對面的圖8之下 腔室空間可以是音室結構872。位於基底860與振膜810 之間的下腔室的空間可經由位於任兩個相鄰的音室支撐體 870之間的多個振膜工作區來產生揚聲器8〇2的共鳴音場。 _ 平面揚聲器802可包括振膜810、開孔電極820、邊框 支撐體（Frame supporting member) 830以及位於開孔電極 820與振膜810之間的多個支撐體84〇。開孔電極82〇位於 振膜810 —側，而振膜810另一侧具有音室結構872，且 基底860及位於振膜810與基底860間的多個支撐體870 形成音室結構872。基底860、支撑體870、以及其包圍的 音室結構872是選擇性的，亦即平面揚聲器單體可以不包 括基底860、支撐體870、以及其包圍的音室結構872。此 13 201220862 rjiyy\jyj5UW 35485twf.doc/n 外，基底860也可以用另一片開孔電極取代，即平面揚聲 器802具有兩片開孔電極，分別位於振膜810的兩側。另， 基底860與振膜810間可直接以邊框支撐體830連結，抑 或基底860與振膜810間可以另一邊框支撑體結合，形成 邊框支樓體830連結開孔電極820與振膜810，而另—邊 框支撐體連結基底860與振膜810。 振膜810可包括駐極體層812及金屬薄膜電極gw。 在某些實施例中，駐極體層812的上表面812a可電轉合邊 框支撐體830及支撐體840，並且駐極體層812的下表面 812b可電搞合上述金屬薄膜電極814。絕緣層（未繒示） 可夾在駐極體層812與電極814之間。 開孔電極820可包括金屬材料、非金屬材料、導電材 料或不導電材料。在一實施例中，開孔電極820亦可由例 如紙或一種極薄（Extremely thin)不導電的材料上，鍍上 一層金屬薄膜在上述紙或不導電的材料上。 又 當開孔電極820包括鍍有一層金屬薄膜層之不導電材 料時，此不導電材料可以是塑膠、橡膠、紙、不導電的布 (棉纖維或聚合物纖維）或其他的不導電材料；並且此金 ，薄獏可以是㉟、金、銀、銅、錄/金雙金屬、氧化銦錫 =ci贿 tin〇xide; IT〇)、氧化銦鋅（μ画 _〇他； )、大分子導電材料聚二氧乙烯噻吩 k olyethylenedioxythiophene ; PEDOT)等等；或合金； 1者^示之材料或其等效材料的任何組合。當開^極 用導電的材料時’此導電的材料可以是金屬（鐵、 201220862 P51990057TW 35485twf.doc/n 綱、㈣衫幻、導電的布（金屬纖維、氧化物金 維、碳纖維或石墨纖維）轉，或錢些㈣或其他材料 的任何組合。 駐極體層812可包括介電材料，此材料可予以處理或 充電而保留靜電荷達-段時間或—個延伸的時間區間，並 且在充電之後於此材料内具有駐電效應或靜電效應。駐極Device), an indispensable device for surge protection in electronic equipment, is often referred to as an "overvoltage protector." The function of the surge protector is to limit the transient overvoltage that breaks into the signal transmission line to the voltage range that the device or system can withstand, protecting the protected device or system from impact and damage. The type and structure of the surge protector varies from application to application, but at least one non-linear voltage limiting component should be included. The basic components used in the surge protector are, for example, a discharge gap, a gas-filled discharge tube, a varistor, a suppression diode, and a choke coil. The surge protector can be, for example, a voltage-limiting protector, which works on the principle of high-impedance when there is no transient over-voltage, but its impedance decreases with the increase of the surge current and voltage, and its current-voltage characteristic is strong. Nonlinear. The components used as such devices are zinc oxide, varistor, suppression diode, Zener diode, and the like. In the above embodiments, the driving interface device of the planar speaker with the pressure limiting function is disclosed. In addition to the capacitor and the transformer component, the voltage limiter and the surge protector can be integrated as a flat speaker. The components of the device, therefore, even if the signal is amplified by the transformer, it can further provide a maximum rated voltage that does not exceed the planar speaker, causing permanent damage to the device. 12 201220862 r j iy^uuj7TW 35485twf.doc/n In the above various embodiments, the planar speaker to be driven, please refer to the structure shown in FIG. 8 for a schematic view of the planar speaker in an embodiment. For diaphragm 81() located between any two adjacent layers of support, planar speaker 802 can have several working areas. Both sides of the diaphragm 810 can define or define their working areas in the same manner in different ways. The illustrated sound chamber structure can have two chamber spaces' to create a resonant sound field or effect of the speaker, one above and one below the diaphragm 810. The louver 802 can have a plurality of supports 840, 870 that can be designed to have a particular shape and placed within the upper and lower chamber spaces to support the aperture electrode 820 and the diaphragm, respectively. 810, and supporting the substrate 860 and the diaphragm 810. In one embodiment, the upper chamber space of Figure 8 may be a sound hole area 842, and the chamber space below Figure 8 opposite the sound hole area 842 may be a sound chamber structure 872. The space of the lower chamber between the substrate 860 and the diaphragm 810 can create a resonance sound field of the speaker 8〇2 via a plurality of diaphragm working areas between any two adjacent sound chamber supports 870. The planar speaker 802 may include a diaphragm 810, an aperture electrode 820, a frame supporting member 830, and a plurality of support bodies 84 located between the aperture electrode 820 and the diaphragm 810. The aperture electrode 82 is located on the side of the diaphragm 810, and the other side of the diaphragm 810 has a sound chamber structure 872, and the substrate 860 and the plurality of supports 870 located between the diaphragm 810 and the substrate 860 form a sound chamber structure 872. The substrate 860, the support 870, and the surrounding chamber structure 872 are optional, i.e., the planar speaker unit may not include the substrate 860, the support 870, and the sound chamber structure 872 enclosed thereby. In addition, the substrate 860 can also be replaced by another aperture electrode, that is, the planar speaker 802 has two aperture electrodes, which are respectively located on both sides of the diaphragm 810. In addition, the base 860 and the diaphragm 810 can be directly connected by the frame support body 830, or the base frame 860 and the diaphragm 810 can be combined with another frame support body, and the frame support body 830 is connected to the aperture electrode 820 and the diaphragm 810. The other frame support body connects the substrate 860 and the diaphragm 810. The diaphragm 810 may include an electret layer 812 and a metal film electrode gw. In some embodiments, the upper surface 812a of the electret layer 812 can electrically couple the rim support 830 and the support 840, and the lower surface 812b of the electret layer 812 can electrically engage the metal thin film electrode 814. An insulating layer (not shown) may be sandwiched between the electret layer 812 and the electrode 814. The aperture electrode 820 may comprise a metallic material, a non-metallic material, a conductive material or a non-conductive material. In one embodiment, the aperture electrode 820 can also be coated with a thin film of metal on the paper or non-conductive material, such as paper or an extremely thin, non-conductive material. When the aperture electrode 820 comprises a non-conductive material coated with a metal thin film layer, the non-conductive material may be plastic, rubber, paper, non-conductive cloth (cotton fiber or polymer fiber) or other non-conductive material; And this gold, thin enamel can be 35, gold, silver, copper, recorded / gold bimetal, indium tin oxide = ci britain x ; xide; IT 〇), indium zinc oxide (μ painting _ 〇 he;), macromolecule Conductive material: polyoxyethylene thiophene k olyethylenedioxythiophene; PEDOT); or the like; or alloy; any combination of materials or equivalent materials thereof. When the conductive material is used for the opening, the conductive material may be metal (iron, 201220862 P51990057TW 35485twf.doc/n, (4) shirt, conductive cloth (metal fiber, oxide gold, carbon fiber or graphite fiber) Turn, or any combination of money (4) or other materials. The electret layer 812 can include a dielectric material that can be treated or charged to retain static charge for a period of time or an extended time interval, and after charging There is a residential or electrostatic effect in this material.
體層!12可，括-層或多層介電層。介電材料的例子包括 聚全氟乙丙烯（Fluorinated hylenepropylene ; FEP )、聚四 氟乙烯（Polytetrafluoethylene ; PTFE )、聚偏二氟乙烯 (Polyvinylidene fluoride ; PVDF)、氟聚合物材料或其他 的適當材料。上述介電質材料可包括具有微米等級或奈米 等級直徑的孔洞。因為駐極體層812可保留靜電荷達一延 伸時間區間之久，並且可在接受充電處理之後具有壓電特 性，所以在振膜内的孔洞可增進傳輸且增強此材料的壓電 特性。在一實施例中’在電暈充電（匸⑽⑽charging)之 後可產生雙極性電荷（Dipolar charges )且保留電荷於介電 材料内以產生駐電效應或靜電效應。 為了提供振膜810的良好張力及/或振動效應，金屬薄 膜電極814可以是很薄的金屬薄膜電極。舉例來說，其厚 度可以在0.2微米與〇.8微米之間或0.2微米與〇.4微米之 間。在某些實施例中可以是大約0.3微米。所繪示之尺度 範圍通常視為「超薄」。 舉具有負電荷的駐極體層812為例，當供應輸入音頻 訊號給具有孔洞的開孔電極82〇及金屬薄膜電極814時， 15 201220862 P51990057TW 35485twf.d〇c/n 輸入訊號之正電壓可對振膜的負電荷產生吸引力，並且輸 入訊號之負電壓可對此單元的負電荷產生排斥力，因而使 振膜810以一方向移動。相雜，當輸入音源訊號的電壓 相位改變時，同樣地正電壓可對振膜的負電荷產生吸引 力’並且負電壓可對此單元的負電荷產生排斥力，因而使 振膜810以前段所述方向之反方向移動。振膜可重複地來 回移動且振動壓縮周圍空氣，以經由不同的方向之不同的 力之互動來產生聲音。換句話說，即開孔電極與振膜根據 音頻號，相互作用而使振膜振動並據以產生對應聲音。 在一實施例中，薄膜850可選擇性地覆蓋揚聲器8〇2 的一邊或兩邊。某些使用狀態也可不需薄膜85〇。薄膜85〇 可以是透氣但防水的，例如由包含膨體聚四氟乙烯 (Expanded polytetrafluoroethylene ； ePTFE )等等之 G0RE-TEX®薄膜所構成。G0RE-TEX®或類似的材料能預 防水及氧的效應’因而避免駐極體層812漏失其電荷及降 低其駐電效應。 振膜810的多個工作區可形成於任兩個相鄰的支撐體 840之間以及上述開孔電極820與振膜81〇之間。上腔室 842的這些工作區可用以產生平面揚聲器go]的共鳴音 %。振膜810的多個工作區可形成於任兩個相鄰的支摔體 870之間以及基底860與振膜810之間。下腔室872的這 些工作區也可用以產生平面揚聲器802的共鳴音場。可調 整支撐體840及支撐體870兩者的室中位置、高度以及形 狀作為揚聲器設計的一部分。此外，支撐體87〇的數目可 201220862 i*Myyuu57TW 35485twf.doc/n 大於、等於或小於支撲體840的數目，並且可直接製造支 撐體840或支撐體870於開孔電極820或基底860之上或 其上方。The body layer! 12 can include a layer or a plurality of dielectric layers. Examples of the dielectric material include Fluorinated hylene propylene (FEP), Polytetrafluoroethylene (PTFE), Polyvinylidene fluoride (PVDF), fluoropolymer materials, or other suitable materials. The above dielectric material may include pores having a micron or nanometer diameter. Because the electret layer 812 can retain static charge for an extended period of time and can have piezoelectric characteristics after being subjected to a charging process, the holes in the diaphragm can enhance transmission and enhance the piezoelectric properties of the material. In one embodiment, "Dipolar charges" can be generated after corona charging (匸(10)(10)charging) and the charge is retained within the dielectric material to create a resident or electrostatic effect. In order to provide good tension and/or vibration effects of the diaphragm 810, the metal film electrode 814 can be a very thin metal film electrode. For example, the thickness can be between 0.2 microns and 〇.8 microns or between 0.2 microns and 〇.4 microns. In certain embodiments it can be about 0.3 microns. The scale range shown is usually considered "ultra-thin". Taking a negatively charged electret layer 812 as an example, when an input audio signal is supplied to the aperture electrode 82 and the metal thin film electrode 814 having holes, the positive voltage of the input signal can be 15 201220862 P51990057TW 35485twf.d〇c/n The negative charge of the diaphragm creates an attractive force, and the negative voltage of the input signal can repel the negative charge of the unit, thereby causing the diaphragm 810 to move in one direction. Compatible, when the voltage phase of the input sound source signal changes, the positive voltage can also attract the negative charge of the diaphragm 'and the negative voltage can generate a repulsive force to the negative charge of the unit, thus causing the diaphragm 810 to Move in the opposite direction of the direction. The diaphragm can repeatedly move back and vibrate to compress the surrounding air to produce sound through interaction of different forces in different directions. In other words, the aperture electrode and the diaphragm interact with each other according to the audio number to vibrate the diaphragm and accordingly generate a corresponding sound. In one embodiment, the film 850 can selectively cover one or both sides of the speaker 8〇2. In some states of use, there is no need for a film 85. The film 85 〇 may be breathable but waterproof, such as a G0RE-TEX® film comprising expanded polytetrafluoroethylene (ePTFE) or the like. G0RE-TEX® or similar materials are capable of pre-water and oxygen effects' thus avoiding electret layer 812 from losing its charge and reducing its electrification effect. A plurality of working areas of the diaphragm 810 may be formed between any two adjacent supports 840 and between the aperture electrodes 820 and the diaphragm 81A. These working areas of the upper chamber 842 can be used to produce a resonance sound % of the planar speaker go]. A plurality of working areas of the diaphragm 810 may be formed between any two adjacent wraps 870 and between the substrate 860 and the diaphragm 810. These working areas of the lower chamber 872 can also be used to create a resonant sound field of the planar speaker 802. The position, height, and shape of the chamber of both the adjustable support 840 and the support 870 are part of the speaker design. In addition, the number of the support bodies 87〇 may be greater than, equal to, or less than the number of the baffle bodies 840 by 201220862 i*Myyuu57TW 35485twf.doc/n, and the support body 840 or the support body 870 may be directly fabricated on the aperture electrode 820 or the substrate 860. Up or above.
音室結構接近振膜810的金屬薄膜電極814的表面， 可藉由考量揚聲器的音頻特性或其他的聽覺或結構的因素 予以設計。音室可包括吸音材料；並且支撐體或音室支樓 體可設計成各種形狀。邊框支撐體83〇所形成的室空間可 在邊框支撐體830之中具有音孔，以便釋放所產生的聲音 的壓力，並且在某些例子中產生較好的音場效應。 士。仏，，、。開孔電極820電壓的驅動電路模組可以與平面揚 =器8犯獨立且電性連接。如此一來，包括散熱元件的驅 動電路模組加上平面揚聲器觀的整體重量與體積將不 =因：’本發明提出一種平面揚聲器裝置，將二聲 路模組整合，並省去驅動電路模組中散熱元 件，以減少整體重量與體積。 即不例為雙音室，本發明亦可為單音室’亦 定本發明明已以實施例揭露如上’然其並非用以限 離本所屬技術領域中具有通常知識者，在不脫 本發明之#可作餅之找與潤飾，故 準。 圍田視後附之申請專利範圍所界定者為 【圖式簡單說明】 17 201220862 r j 35485twf.doc/nThe chamber structure is close to the surface of the metal film electrode 814 of the diaphragm 810 and can be designed by considering the audio characteristics of the speaker or other acoustic or structural factors. The sound chamber may include a sound absorbing material; and the support body or the sound chamber support body may be designed in various shapes. The chamber space formed by the bezel support 83 can have sound holes in the bezel support 830 to release the pressure of the generated sound and, in some instances, produce a better sound field effect. Shi. Hey,,,. The driving circuit module of the opening electrode 820 voltage can be independently and electrically connected to the plane. In this way, the overall weight and volume of the driving circuit module including the heat dissipating component plus the planar speaker view will not be as follows: 'The present invention proposes a planar speaker device that integrates the two-channel module and eliminates the driving circuit mode. Cooling components in the group to reduce overall weight and volume. That is, the present invention is not limited to the present invention. ## can be used as a cake to find and retouch, so accurate. The definition of the patent application scope attached to the field is defined as [Simplified illustration] 17 201220862 r j 35485twf.doc/n
在此加上附圖以提供本發明的進一步理解，並且予 以，入本發明而構成本說明書的一部分。附圖繪示本發明 的實施例且連同其說明用以解釋本發明的原理。 X 圖1為依照本發明一實施例的平面揚聲器之驅動介 面裝置之架構示意圖。 圖2A為運用本發明一實施例的平面揚聲器之驅動 介面裝置的架構示意圖，而圖2B為運用本發明實施例的 平面揚聲器之驅動介面裝置之結構示意圖。 圖3A〜7A為運用本發明不同實施例的平面揚聲器 之驅動介面裝置的架構示意圖，而圖3B〜7B為運用本發 明不同實施例的平面揚聲器之驅動介面裝置之電路結構示 意圖。 圖8為說明本發明一實施例中的平面揚聲器之示意 圖。 【主要元件符號說明】 100 :音響驅動裝置 112與114:音源訊號 120、120A、12〇b、120C、120D、120E、120F :驅動 介面裝置 121 :電容器 122與124 :驅動訊號 123 :變壓器 125 :限壓器 201220862 rji^>uuj7TW 35485twf.doc/n 127 :保護電路 132 :匹配電阻 134 :等效負載電容 802 :平面揚聲器 810 :振膜 812 :駐極體層 812a :上表面 812b :下表面 φ 814 :金屬薄膜電極 820 :開孔電極 830 :邊框支撐體 840 :支撐體 842 :傳聲孔區域 850 :薄膜 860 :音腔基底 870 :支撐體 872 :音室結構 • 19The drawings are included to provide a further understanding of the invention and are intended to be part of the invention. The drawings illustrate embodiments of the invention and, together with 1 is a schematic block diagram of a driving interface device for a planar speaker according to an embodiment of the invention. 2A is a schematic structural view of a driving interface device for a planar speaker according to an embodiment of the present invention, and FIG. 2B is a schematic structural view of a driving interface device for a planar speaker according to an embodiment of the present invention. 3A to 7A are schematic diagrams showing the construction of a driving interface device for a planar speaker according to various embodiments of the present invention, and Figs. 3B to 7B are schematic diagrams showing the circuit configuration of a driving interface device for a planar speaker according to various embodiments of the present invention. Fig. 8 is a schematic view showing a planar speaker in an embodiment of the present invention. [Main component symbol description] 100: Audio driving devices 112 and 114: sound source signals 120, 120A, 12〇b, 120C, 120D, 120E, 120F: driving interface device 121: capacitors 122 and 124: driving signal 123: transformer 125: Voltage limiter 201220862 rji^>uuj7TW 35485twf.doc/n 127: protection circuit 132: matching resistor 134: equivalent load capacitance 802: plane speaker 810: diaphragm 812: electret layer 812a: upper surface 812b: lower surface φ 814: metal film electrode 820: aperture electrode 830: frame support body 840: support body 842: sound hole area 850: film 860: sound chamber substrate 870: support body 872: sound chamber structure • 19